ALLEN PARK, Mich. -- Jim Caldwell rarely talks about the specifics of injuries, but he made an exception this time.
Detroit guard T.J. Lang was going through the concussion protocol Thursday, three days after he played in a win at Green Bay . Without being asked, Caldwell elaborated on Lang's situation at the end of his news conference, in an effort to avoid confusion.
Caldwell said it wasn't anything that had happened to Lang in practice.
"After the ballgame was over with, sometimes these things don't manifest themselves (for) between 24 and 72 hours, and this is one of those cases," Caldwell said.
"He's fine, no issues, all the way up until (Wednesday) we start practice, and once practice starts, he gets ill. So, we take him out of practice, get him inside and then the doctors don't come until after we finish with obviously submitting our medical report."
Lang was listed on Wednesday's injury report with an undisclosed illness.
"After they had an opportunity to take a look at him, determined that he should be placed in the concussion protocol," Caldwell said. "So that's where he is at this particular point in time."
Lang has started seven games this season and missed one with back issues. Detroit's offensive line has looked better the past couple of games, allowing only three sacks after giving up 17 over the previous three games. The Lions have struggled near the goal line, however, and their running game still isn't consistent.
Offensive coordinator Jim Bob Cooter joked that whether Lang plays or not, the Lions will have five offensive linemen on the field.
"T.J.'s a heck of a player," Cooter said. "I'm not going to speak about injury specifics or anything like that, but hey, he's a really, really good player and if he's up, great. If he's not, we got guys we trust to go in there and play good football."
Detroit defensive end Ziggy Ansah (back) missed practice Thursday along with Lang, and so did linebacker Jalen Reeves-Maybin (ankle). Safety Don Carey (knee), wide receiver Kenny Golladay (hamstring) and tackle Greg Robinson (ankle) were limited.
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